A rock 'n' roll soundtrack for the '70s filled the air at Horseshoe Casino's outdoor venue, The Shoe, on Sunday night as Peter Frampton and the Doobie Brothers played to a sold-out audience.

Both acts played it safe, giving the mostly baby boomer crowd what they came for – stirring versions of their familiar hits.

Frampton, the former Cincinnati resident now living in Nashville, may be more famous in these parts lately for his collaboration with the Cincinnati Ballet, as much as his iconic arena-rock hits. Frampton has a seven-cut CD ("Hummingbird in a Box") out this week with songs inspired by his ballet compositions. His music was performed by the ballet here and in New York in the last year. But Frampton never mentioned the release on stage and steered clear of trying any of the ballet pieces on the rock audience, perhaps figuring they fit into a different musical "box."

Opening with "You Had To Be There," Frampton quickly got out the talk box for "Show Me the Way" and his other anthems such as "Baby, I Love Your Way," "Black Hole Sun," closing with his obligatory endless jam on "Do You Feel Like We Do."

Pam and Joel Roadruck, celebrating their 35th Anniversary (their first date was a Doobie Brothers concert in 1975) at the Horseshoe Casino for the Doobie Brothers and Peter Frampton concert on June 22, 2014.
Jennifer Denham

Frampton, even with his silver-haired professorial look, remains the consummate guitar hero, every bit as accomplished and sizzling on his Gibson electric, backed by a five-piece band. What was unexpected is Frampton's voice is perhaps getting more interesting with age. The 64-year-old sings in a more measured, less hurried style, almost like a jazz singer where diction counts. The pristine vocals now match his immaculate guitar work. That was most evident on "Lines on My Face," which Frampton performed giving new life to the haunting power ballad.

It was Frampton's first time playing the outdoor casino venue.

"This is a pretty nice place. I voted for it," he said referring to the ballot initiative that approved casinos for Ohio. Frampton also quipped that he voted for President Obama while he lived here (it was his first vote as a naturalized U.S. citizen). That comment drew a smattering of boos from the anti-Obama audience faction. Frampton seemed surprised by the political dissension and quickly diffused the situation by saying, "Of course, we can all agree music is one thing that brings us together."

That was perhaps most evident in the encore with his achingly beautiful cover of George Harrison's "While My Guitar Gently Weeps," which has become a closing staple for Frampton.

The Doobie Brothers opened the night still fronted by Tom Johnston and Patrick Simmons, band founders/guitarists/songwriters, bringing a wonderful eight-piece band that proved one of the surprising high points of the night. The tremendous roots-boogie group breathed fresh licks into familiar tunes. It showcased sax player Mark Russo, who blasted away on several songs, sometimes taking lead from the guitars.

It was something of a make-good set for the band, since their show was a rainout at the venue last summer. The Doobies stuck mostly to their early hits, staying away from the soft-rock period when Michael McDonald joined the group. They did perform "Taking It to the Streets" with Simmons valiantly trying to hit McDonald's high notes but not quite getting there.

The audience was certainly content with the Simmons-Johnston stable of more rugged rockers, such as "Rockin' Down the Highway," "Black Water," "Long Train Running," "China Grove," and, for the encore, "Listen to the Music." For the finale, the band was joined on vocals and guitar by Simmons' son, Patrick Jr., who has opened occasionally for his father's shows.

The Doobie Brothers perhaps get overlooked as a contemporary influence, but their mix of blues, R&B, bluegrass and country-rock pretty much defines what we now call the Americana genre. Indeed, so many country-pop artists today cite the Doobies as an influence that the band's next move is to record with them. The band is working on a new greatest hits album with star country performers interpreting their songs such as Toby Keith, Brad Paisley, Zac Brown, Sara Evans, and Chris Young.